Use Rococoa to get list of macOS voices including gender info

[bertfrees]

See:

• https://github.com/iterate-ch/rococoa/blob/a7394418403b8211428d02d752803e5dd5547a47/rococoa/rococoa-contrib/src/main/java/org/rococoa/contrib/appkit/NSSpeechSynthesizer.java
• https://github.com/iterate-ch/rococoa/blob/a7394418403b8211428d02d752803e5dd5547a47/rococoa/rococoa-contrib/src/main/java/org/rococoa/contrib/appkit/NSVoice.java
• https://github.com/iterate-ch/rococoa/blob/a7394418403b8211428d02d752803e5dd5547a47/rococoa/rococoa-contrib/src/test/java/org/rococoa/contrib/appkit/NSVoiceTest.java
• https://github.com/bertfrees/tts-manager/blob/master/src/org/bertfrees/tts/mac
• https://stackoverflow.com/questions/6655310/mac-os-x-text-to-speech-genders